Potential of Core-Collapse Supernova Neutrino Detection at JUNO

JUNO is an underground neutrino observatory under construction in Jiangmen, China. It uses 20kton liquid scintillator as target, which enables it to detect supernova burst neutrinos of a large statistics for the next galactic core-collapse supernova (CCSN) and also pre-supernova neutrinos from the nearby CCSN progenitors. All flavors of supernova burst neutrinos can be detected by JUNO via several interaction channels, including inverse beta decay, elastic scattering on electron and proton, interactions on C12 nuclei, etc. This retains the possibility for JUNO to reconstruct the energy spectra of supernova burst neutrinos of all flavors. The real time monitoring systems based on FPGA and DAQ are under development in JUNO, which allow prompt alert and trigger-less data acquisition of CCSN events. The alert performances of both monitoring systems have been thoroughly studied using simulations. Moreover, once a CCSN is tagged, the system can give fast characterizations, such as directionality and light curve

Detection of the Diffuse Supernova Neutrino Background with JUNO

As an underground multi-purpose neutrino detector with 20 kton liquid scintillator, Jiangmen Underground Neutrino Observatory (JUNO) is competitive with and complementary to the water-Cherenkov detectors on the search for the diffuse supernova neutrino background (DSNB). Typical supernova models predict 2-4 events per year within the optimal observation window in the JUNO detector. The dominant background is from the neutral-current (NC) interaction of atmospheric neutrinos with 12C nuclei, which surpasses the DSNB by more than one order of magnitude. We evaluated the systematic uncertainty of NC background from the spread of a variety of data-driven models and further developed a method to determine NC background within 15\% with {\it{in}} {\it{situ}} measurements after ten years of running. Besides, the NC-like backgrounds can be effectively suppressed by the intrinsic pulse-shape discrimination (PSD) capabilities of liquid scintillators. In this talk, I will present in detail the improvements on NC background uncertainty evaluation, PSD discriminator development, and finally, the potential of DSNB sensitivity in JUNO

Real-time Monitoring for the Next Core-Collapse Supernova in JUNO

Core-collapse supernova (CCSN) is one of the most energetic astrophysical events in the Universe. The early and prompt detection of neutrinos before (pre-SN) and during the SN burst is a unique opportunity to realize the multi-messenger observation of the CCSN events. In this work, we describe the monitoring concept and present the sensitivity of the system to the pre-SN and SN neutrinos at the Jiangmen Underground Neutrino Observatory (JUNO), which is a 20 kton liquid scintillator detector under construction in South China. The real-time monitoring system is designed with both the prompt monitors on the electronic board and online monitors at the data acquisition stage, in order to ensure both the alert speed and alert coverage of progenitor stars. By assuming a false alert rate of 1 per year, this monitoring system can be sensitive to the pre-SN neutrinos up to the distance of about 1.6 (0.9) kpc and SN neutrinos up to about 370 (360) kpc for a progenitor mass of 30$M_{\odot}$ for the case of normal (inverted) mass ordering. The pointing ability of the CCSN is evaluated by using the accumulated event anisotropy of the inverse beta decay interactions from pre-SN or SN neutrinos, which, along with the early alert, can play important roles for the followup multi-messenger observations of the next Galactic or nearby extragalactic CCSN.Comment: 24 pages, 9 figure

A Simple Monetary Model of a Shortage Economy

During the transition from a centrally planned economy to a market economy, many countries seem to have experienced some degree of macroeconomic instability. This paper attempts to provide a theoretical explanation of this phenomenon. The paper develops a simple monetary model and shows how macroeconomic stability can be achieved in a rigid centrally planned economy, despite the inherent structural imbalances and irrational price system. On the other hand, the study shows that without hardening enterprise budget constraints, wage and price decontrol tends to destablize the economy and may lead to persistent budget deficits and inflation. The paper also provides a rigorous analysis of household savings and money demand in a shortage economy, and clarifies the somewhat confusing concept of “monetary overhang” in the literature.Price controls;Centrally planned economies;Economic models;wage, black market, wages, inflation, money supply, wage control, macroeconomic stability, wage level, wage rate, price level, high inflation, wage increase, wage increases, benefits, aggregate demand, macroeconomic control, wage policy, wage costs, inflation rate, printing money, wage policies, money stock, wage controls, inflation stabilization, relative prices, profit sharing, real wages

Terms of Trade and Current Account Dynamics: A Methodological Critique.

This paper suggests that the recent intertemporal studies concerning the implications of terms-of-trade deterioration on the current account of a small open economy may suffer from significant methodological deficiencies. The study demonstrates that, while the assumption of a small open economy represents a legitimate modeling simplification, the analysis of the impact of perturbation of the terms of trade on the current account of this small open economy is methodologically erroneous. In particular, the paper demonstrates that a given pattern of terms-of-trade deterioration may be associated with opposing evolutionary patterns of the current account of this small economy. Copyright 1994 by Economics Department of the University of Pennsylvania and the Osaka University Institute of Social and Economic Research Association.

Can the Release of a Monetary Overhang Trigger Hyperinflation?

It is widely feared that, once prices are decontrolled in the formerly centrally–planned economies, households’ release of previously accumulated money will trigger a hyperinflation. This paper finds, instead, that whether a country’s fiscal, monetary, and labor market policies are destabilizing typically does not depend on the money stock. However, the release of a monetary overhang can precipitate a large initial real wage shock. To the extent such a shock is not feasible politically, there is a motive for monetary reform, which must be weighed against the cost of reduced public confidence in money.Price decontrols;Centrally planned economies;Economic models;wage, wages, inflation, real wages, money stock, inflation rate, high inflation, benefits, salaries, wage inflation, wage adjustment, wage controls, nominal interest rate, inflation rates, money supply, price level, real value, minimum wages, rates of inflation, wage adjustments, inflationary spiral, real interest rate, monetary phenomena, rate of inflation, wage taxes, inflationary impact, stock of money, wage freeze, wage increases, real output, control of inflation, expectations of inflation, wage earners, real money, wage indexation, wage equations

Inflation and stabilization in transition economies: An analytical interpretation of the evidence

A simple model is developed to understand inflationary pressures and stabilization in non-market economies. It is shown that in the typical planned economy, the endogeneity of the money supply and the over-determination of the system (given that both prices and wages are set by the planners) imply that a permanent increase in wages leads to an ever-increasing monetary overhang. The model also suggests that price liberalization should lead to a price level overshooting provided that wages remain a nominal anchor. In light of the model, the paper reviews the inflation and stabilization experiences of several transition economies in Eastern Europe and the former Soviet Union. The paper concludes that (i) transition economies have suffered from essentially the same inflationary pressures as did planned economies, and (ii) the exchange rate has been more effective than money as a nominal anchor in reducing inflationinflation, stabilization, transition economies,